Attachment for telephones.



J. W. NILSSON.

ATTACHMENT FOR TELEPHONES.

APPLICATION FILED MAY 8, 1909.

955 1 9 Patented; Apr. 19, 1910.

3 SHEETS-SHEET 1;

Wiinoosu.

J. W. NILSSON.

ATTACHMENT FOR TELEPHONES.

APPLICATION FILED MAY 8, 1909.

955,190. Patented Apr. 19, 1910.

3 SHEETS-SHEET 3.

Witnmozo JW JOHN W. NILSSON, OF BALFOUR, NORTH DAKOTA.

ATTACHMENT FOR TELEPI-ION ES.

Specification of Letters Patent.

Patented Apr. 19, 1910.

Application filed May 8, 1909. Serial No. 494,730.

To all whom it may concern:

Be it known that I, JOHN W. NILssoN, a citizen of the United States,residing at Balfour, in the county of McI-Ienry, State of North Dakota,have invented certain new and useful Improvements in Attachments forTelephones; and I do hereby declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

This invention relates to telephone circuits and more especially to adevice for detecting a third party on a telephone circuit.

More particularly the invention is an attachment for telephones.

The principal object of the invention is to provide an audible signalwhich will inclicate to a person using any one of the tele phones in atelephone system the presence of an auditor at another telephone of thatsystem.

Another object of the invention is to indicate to a person using any oneof the telephones of a telephone system, the number of .the telephoneanswering his call, thereby detecting whether or not the has responded.

With the above and other objects in view, the invention consists, ingeneral, of an attachment for telephones so arranged as to renderaudible any attempt to listen through any one of said telephones to suchother person as may be in conversation and at the same time to indicatewhat telephone is being used to intercept the conversation.

The invention further consists in certain novel details of constructionand combinations of parts, hereinafter fully described, illustrated inthe accompanying drawings, and specifically set forth in the claims.

In the accompanying drawings, like characters of reference indicate likeparts in the several views, and :Figure l is a front elevation of anattachment for telephones constructed in accordance with this invention,the front of the casing of the device being removed to show theinterior. Fig. 2 is a section on the line 22 of Fig. 1. Fig. 3 is asection on the line 33 of Fig. 1. Fig. 4 is a detail section on the line44: of Fig. 1. Fig. ,5 is an enlarged detail view of the guard plate.Fig. 6 is an enlarged detail perspective of the bell actuating frame.Fig. 7 is an enlarged detail showing the arrangement of one of thehammers. I

right telephone The device has here been shown as applied to an ordinarytelephone of the wall or boX type such as indicated by the letter A.This telephone is equipped with the usual transmitter b and receiver 0,all of these parts being of the ordinary and well known form.

The numeral 10 indicates the usual telephone receiver fork which isadapted to be raised by a spring 11 when the receiver is removed fromthe fork. This telephone receiver fork is provided with a contactclosing block 12 arranged to close the usual line contact 13. Upon thereceiver fork 10 and opposite the slot 14 through which the fork movesthere is provided a guard plate 15 provided on its upper edge with apair of spaced upstanding members 16 adapted to lie on either side ofthe receiver fork. One of these members is provided with a set screw 17in order to clamp the receiver fork firmly and prevent accidentaldetachment of the plate. Each of the members 16 is provided with anoutwardly extending perforated ear 18 for purposes hereinafter to bedescribed.

The signaling mechanism proper comprises a pair of bells l9 and 20,preferably of different tone and whereof 19 is here shown as a plainround bell while 20 is a coil of tempered steel wire such as is commonlyfound in the cathedral gongs of clocks. In order to ring these bellsthere is provided a pair of bell crank levers 21, one of these leversbeing adjacent each of the bells and each of the levers being providedwith a hammer head 22. These levers are pivoted on pivot posts 23secured in the back of the casing and each of these pivot posts issurrounded by a spiral spring 24 one end whereof is fixed to the postand the other end whereof operates to throw the hammer head 22 againstthe respective bells when moved away therefrom by the mechanism now tobe described.

At 25 are arranged levers pivoted interme diate their ends each havingone end contacting loosely with the end of the bell crank lever 21 sothat by moving the contacting end of the lever 25 upward the bell cranklever has the hammer pushed away from the gong until it is disengagedfrom the end of the lever 25 when the spring 24 forces it quicklybackward and strikes the gong.

At 26 is shown a pair of brackets each of which is provided with guideears 27 through which pass rods 28 connected at their top by a plate 29and at the bottom by a plate 30. Each. of these plates extend outwardfrom the rod and on their outer ends support a ringing bar 31 providedwith a series of projecting pins 32 on the upper end of the bar and asecond series of projecting pins 33 on the lower end of the bar. Thesepins are arranged to contact alternately with the upper lever 25 and thelower lever 25 so that these levers are alternately actuated.Furthermore, these pins are varied in number and positioned so that thebells may each be struck a desired number of times as the frameincluding the bars and pins is moved through the ears 27. In order to0perate this frame the plate 30 is provided with an eye 30 wherethroughextends the end of a lever 32 pivotally mounted on a pivot post 33. Theopposite end of this lever 32 is pivotally connected to a bar 34. Thisbar 3st extends downward through a suitable opening in the casing andtelephone box and passes through one of the cars 18 being slidabletherein. In order to limit the sliding motion the bar 34 is providedwith a head which is adapted to contact with the under side of its car18 to limit. the upward motion of said bar through the ear and tocontactwith the upper side ofthe fork to limit the downward motion ofthe bar through the The amount of this movement is so arranged thatprior to the move ment of the bar 34: the contacts 13 are closed by theaction of the closing block 12. It will be thus seen that before theringing apparatus is actuated the contactwill be closed and thetelephone thrown into circuit. In order that this movement may not takeplace in a too rapid manner there is provided a gear 36 having V-shapedteeth 37. This gear is pivoted on a post 38 and is freely movablethereon. An arm 39 is also pivoted on the post 38 being likewise freelymovable thereon. The free end of the arm 39 is pivotally attached to therod 34: which extends up ward above the point of its attachment to thelever 32 for this purpose. The rod 3% extends still farther upward andis provided at its upper end with an eye 4-0 to receive the lower end ofa coil spring 41 which is attached at its upper end to a clip &2 mountedon the top of the casing. On the arm 39 is pivotally mounted a pawl 4-3which is normally pressed in the direction of the gear 36 by means of aspring 44. This gear 36 meshes with a gear and the gear 36 is a largegear while the gear 4:5 is preferably a. pinion. The gear 45 is freelyrotatable around a stub axle or post 16 and has attached thereto a largegear l7.

At etS is indicated a bracket supporting a freely rotatable shaft 49which is held in the bracket by means of a collar 50 and this shaft hasfixed on its outer end a gear 51 which meshes with the gear 17. Thisshaft 49 is provided with a transverse opening 52 l wherein is slidablymounted an arm 53 car- I rying on one end a weight 5e and having at theother end a collar Between the collar and the shaft 19 is mounted acompression spring 56. By reason of this construction as the pawl e4engages with the teeth 37 the wheel 36 will be rotated when- I ever thereceiver is removed from the receiver fork and the latter moves upward,this effect taking place as soon as the bar 34- begins to move. As thisgear rotates it will in turn rotate the gear 15 which carries with itthe gear 17 and rotates the gear 51.

If this rotation is more rapid than desired the weight 54 will draw thebar through the opening 52 and thus act as a governor by describing acircle of greater radius as the wheel 51 turns. It is obvious toaccomplish this purpose that the wheel 51 must have a high speed ofrotation relative to the wheel 36 and to this end the wheels36 and t7are provided with a large number of teeth while the wheels 15 and 51 areprovided with a small number of teeth.

In order to hold the wheel 36 locked from movementuntil the removal ofthe receiver from the fork there is provided a pair of guides 5twherethrough extends a rod 58. This rod 58 passes through the remainingear 1S and is held rigidly therein by means of upper and lower nuts 59.At (30 is a lever provided with a hook end (31 arranged to engage theteeth 37 of the gear 30. This lever is also provided with an end (32arranged to l lie normally in the path of the bar 58. By thisarrangement the hook (31 normally engages with the teeth 37, a spring(33 being provided for the purpose of holding the hook in such cont-act.IVhen however, the receiver is removed from the fork the fork l risesand carries with it the bar 58 which strikes the free end (32 of thelever and disengages the hook (31 from the teeth 37. This permits theaction of the pawl tl: on these teeth with the result before described.

In order to render the ringing of the bells 19 and 20 audible on thetalking circuit within the casing is provided a receiver 64: of anydesired form which is connected with the circuit of the telephone bymeans of a wire 65.

It will now be observed that as soon the receiver fork is permitted torise by the removal of the receiver the first action that takes placewill be the release of the hook 61 from the teeth 37 and thesimultaneous closing of the circuit. lVhen this has been accomplishedthe bar 34 will be raised and draw the frame which actuates the lever 25downward thus ringing the bells. This action is dampened however by thegovernor i ball 54; so that it takes place slowly and the bells are rungdistinctly thus preventing confusion in the signals.

There has thus been provided a simple and eflicient device of thecharacter described and for the purpose specified.

It is obvious that many minor changes may be made in the form andconstruction of this invention without departing from the materialprinciples thereof. It is not therefore desired to confine the inventionto the exact form herein shown and described, but it is wished toinclude all such as properly come within the scope of the appendedclaims.

Having thus described the invention, what is claimed as new, is

1. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork, and agovernor mechanism for regulating the speed of said signalsimultaneously operable with said signaling mechanism by said actuatingmeans.

2. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork, and agovernor mechanism for regulating the speed of said signalsimultaneously operable with said signaling mechanism by the actuatingmeans, said governor mechanism embracing a train of gears operable bysaid actuating mechanism, and an inertia governor connected to androtating with the last gear of said train.

3. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork, and agovernor mechanism for regulating the speed of said signalsimultaneously operable with said signaling mechanism by the actuatingmeans, said governor mechanism embracing a train of gears, a ratchetcarried by said actuating mechanism and arranged to rotate the firstgear of said train, and an inertia governor connected to and rotatingwith the last gear of said train.

4. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork, agovernor mechanism embracing a train of gears, a ratchet carried by saidactuating means and arranged to rotate the first gear of said train, ashaft revoluble with the last gear of said train and provided with atransversely disposed aperture, a bar projecting through said aperture,a weight carried on one end of the bar, and a spring on the other end ofthe bar normally forcing said weight toward the shaft. I

5. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork andoperated by the lifting of said fork, a governor mechanism forregulating the speed of said signal simultaneously operable with saidsignaling mechanism and a locking element normally holding the governormechanism from movement and operable to release the bar to the actuationof said governor mechanism.

6. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork andoperated by the raising of said fork, a governor mechanism forregulating the speed of said signal simultaneously operable with saidsignaling mechanism by the actuating means, said governor mechanismembracing a train of gears operable by said actuating mechanism, aninertia governor connected to and rotating with the last gear of saidtrain, and a locking ele ment for said train operable in advance of themovement of the signaling mechanism to release the train from movementof the governor.

7. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork andoperated by the raising of said fork, a governor mechanism forregulating the speed of said signal simultaneously operable with saidsignaling mechanism by the' actuating means, said governor mechanismembracing a train of gears, a ratchet carried by said actuatingmechanism and arranged to rotate the first gear of said train, aninertia governor connected to and rotating with the last gear of saidtrain, and a locking element normally holding said train of gears frommovement and operable by the raising of the telephone forks to re leasethe gears prior to their actuation by the ratchet.

8. In a telephone attachment, an audible signaling mechanism, actuatingmeans for said signaling mechanism attachable to a telephone fork andoperable by the raising of said fork, a governor mechanism embracing atrain of gears, a ratchet carried by said actuating means and arrangedto rotate the first gear of said train, a shaft revoluble with last gearof said train and provided with a transversely disposed aperture, a barprojecting through said aperture, a weight carried on one end of thebar, a spring 011 the other end of the bar normally forcing said weighttoward the shaft, and a locking element normally holding said train ofgears from movement and operable by the raising of said fork, saidlocking element being arranged to release the gears prior to theiractuation by said ratchet.

In testimony whereof, I affix my signature, in presence of twowitnesses.

JOHN W. NILSSON.

Witnesses:

S. L. KEEN, E. J. WIOK.

